Sets cookie(s).

Can be a single cookie object or an array of cookies:

```js
I.setCookie({name: 'auth', value: true});

// as array
I.setCookie([
  {name: 'auth', value: true},
  {name: 'agree', value: true}
]);
```

@param {Cookie|Array<Cookie>} cookie a cookie object or array of cookie objects.
@returns {void} automatically synchronized promise through #recorder
